US6172442B1 - Disk-type brushless single-phase DC motor - Google Patents

Disk-type brushless single-phase DC motor Download PDF

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Publication number
US6172442B1
US6172442B1 US09/191,993 US19199398A US6172442B1 US 6172442 B1 US6172442 B1 US 6172442B1 US 19199398 A US19199398 A US 19199398A US 6172442 B1 US6172442 B1 US 6172442B1
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United States
Prior art keywords
armature coil
rotor magnet
cogging
apexes
stator yoke
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Expired - Fee Related
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US09/191,993
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English (en)
Inventor
Chang Keun Jun
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Samsung Electro Mechanics Co Ltd
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Samsung Electro Mechanics Co Ltd
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Assigned to SAMSUNG ELECTRO-MECHANICS CO., LTD. reassignment SAMSUNG ELECTRO-MECHANICS CO., LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: JUN, CHANG KEUN
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K21/00—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets
    • H02K21/12—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets
    • H02K21/24—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets with magnets axially facing the armatures, e.g. hub-type cycle dynamos
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K29/00—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
    • H02K29/03—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with a magnetic circuit specially adapted for avoiding torque ripples or self-starting problems
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K3/00—Details of windings
    • H02K3/04—Windings characterised by the conductor shape, form or construction, e.g. with bar conductors
    • H02K3/28—Layout of windings or of connections between windings

Definitions

  • the present invention relates to a disk-type brushless single-phase DC motor, and more particularly to a disk-type brushless single-phase DC motor including an armature coil attached to a stator yoke of a stator in such a fashion that it faces the lower surface of a rotor magnet having a plurality of alternating N and S poles, the armature coil having a closed loop structure provided with a plurality of uniformly spaced apexes, and cogging generating protrusions of a miniature size protruded from the stator yoke at positions spaced in a rotation direction of the rotor magnet from respective apexes of the armature coil by an angle corresponding to 1 ⁇ 4 of an angular width of one pole, thereby being capable of achieving an improvement in drive efficiency.
  • disk-type brushless single-phase DC motors are used in miniature fan motors for simple rotating appliances requiring no precise rotation, for example, office appliances such as computers.
  • a multipolar rotor magnet 310 is mounted on the lower surface of the rotor 300 within the rotor 300 .
  • the multipolar rotor magnet 310 has a plurality of alternating N and S poles.
  • the upper end of the shaft 200 is fixedly mounted to the central portion of the rotor 300 .
  • the shaft 200 extends downwardly through a bearing housing 110 upwardly protruded from the central portion of the housing 100 in such a fashion that it is rotatably supported by bearings mounted in the bearing housing 110 .
  • the upper end of the bearing housing 110 has a stepped structure in order to fixedly mount a stator 400 thereon.
  • the stator 400 mainly includes a printed circuit board 410 , a stator yoke 420 laid on the printed circuit board 410 , and armature coils 430 attached to the upper surface of the stator yoke 420 by means of an adhesive.
  • the driving of the disk-type brushless single-phase DC motor having the above mentioned configuration is achieved by a rotation of the rotor 300 carried out by an electromagnetic force generated between the armature coils 430 of the stator 400 and the rotor magnet 310 .
  • a coil torque 600 is generated between the armature coils 430 and the rotor magnet 310 by the electromagnetic force, as shown in FIG. 9 .
  • the coil torque exhibits a maximum value at the middle portion of each pole in the rotor magnet 310 and decreases gradually as the pole extends from the middle portion thereof to each lateral end thereof.
  • the coil torque becomes zero at each lateral end of each pole, thereby causing the rotor 300 to stop.
  • a cogging generating means is provided for a magnetic start-up at such a dead point.
  • Such a cogging generating means provides a cogging force serving as a load against the coil torque.
  • a cogging force is adapted to increase the minimum coil torque while decreasing the maximum coil torque, thereby obtaining a substantially uniform torque. That is, a cogging torque, which has a waveform 700 in FIG. 9, is generated simultaneously with the generation of the coil torque, which has a waveform 600 in FIG. 9, thereby obtaining an ideal resultant torque which has a waveform 800 in FIG. 9 .
  • the cogging torque which serves as a load against the coil torque, has an output level inversely proportional to the output level of the coil torque, thereby reducing the variation in the resultant torque. As a result, the motor can drive stably.
  • a variety of motors provided with such a cogging means have been proposed in, for example, U.S. Pat. No. 4,620,139, U.S. Pat. No. 4,757,222, and Japanese Patent Publication No. Heisei 7-213041.
  • the cogging means disclosed in the patents generates an appropriate cogging torque serving as a load against a coil torque. In accordance with a combination of the cogging torque and coil torque, an ideal resultant torque is obtained.
  • the coil torque and cogging torque exhibit a phase difference corresponding to about 1 ⁇ 4 of the pole width therebetween. Accordingly, the cogging generating means is arranged at a position where the coil torque is zero during a rotation of the rotor.
  • the cogging generating means comprises iron cores 440 coupled to or fitted to the stator yoke 420 in such a fashion that they are protruded from the stator yoke 420 toward the rotor magnet 310 .
  • the cogging generating means may be provided by cutting out opposite arc-shaped peripheral portions of the stator yoke 420 , as shown in FIG. 11 .
  • the cogging generating means comprises arc-shaped cutouts 450 .
  • it is difficult to determine an accurate position of the cogging generating means because the position of the cogging generating means has an inseparable relation with the attachment position of the armature coil.
  • an accurate position for installing the cogging generating means thereon is first determined with respect to each armature coil 430 attached to the stator coil 420 .
  • the coupling or fitting of the iron core 440 to the stator coil 420 is carried out at the determined position.
  • those cutouts are formed at positions determined as above, respectively.
  • the position determination for the cogging generating means is very difficult unless a jig is used.
  • the cogging generating means comprises magnetic members 460 as shown in FIG. 12 .
  • Each magnetic member 460 is positioned at an angle ⁇ (0 ⁇ , where ⁇ is an electrical angle and equal to 180°) from the dead point.
  • the magnetic members have a screw construction so that they also serve as a fixing means for fixing the printed circuit board 410 and stator yoke 420 to each other.
  • the screw members preferentially have the function for fixing the printed circuit board 410 and stator yoke 420 to each other over the cogging generating function. For this reason, after the printed circuit board 410 and stator yoke 420 are fixed to each other, the screw members may have different gaps with respect to the associated rotor magnets 310 , respectively. As a result, the cogging torque generated by the cogging generating means may vary for different screw members.
  • an object of the invention is to provide a disk-type brushless single-phase DC motor including an armature coil arranged on a stator yoke and having a shape capable of generating a maximized effective coil torque, and cogging generating protrusions respectively arranged at positions spaced from apexes of the armature coil by a desired angle while being integral with the stator yoke, thereby being capable of stably outputting an ideal drive torque even when a smaller amount of current is supplied.
  • Another object of the invention is to provide a disk-type brushless single-phase DC motor including cogging generating protrusions capable of appropriately coping with a variation in the use purpose of the motor by a simple variation in the structure thereof while generating an optimum torque.
  • Another object of the invention is to provide a disk-type brushless single-phase DC motor capable of generating a stable and sufficient drive torque even when the amount of supply current is minimized.
  • a disk-type brushless single-phase DC motor comprising a single armature coil attached to a stator yoke of a stator, the armature coil having a closed loop structure.
  • the armature coil has a plurality of uniformly spaced apexes corresponding in number to 1 ⁇ 2 of the number of poles in a rotor magnet.
  • the armature coil also has curved sides each connecting neighboring apexes of the armature coil. Cogging generating protrusions are protruded from the stator yoke at positions spaced in a rotation direction of the rotor magnet from respective apexes of the armature coil by a desired angle.
  • the cogging generating protrusions correspond in number to the apexes of the armature coil and are uniformly spaced from one another.
  • FIG. 1 is a sectional view illustrating a disk-type brushless single-phase DC motor according to the present invention
  • FIG. 2 is an exploded perspective view of the disk-type brushless single-phase DC motor shown in FIG. 1;
  • FIGS. 3 a to 3 d are plan views respectively illustrating various embodiments of an armature coil according to the present invention.
  • FIGS. 4 a and 4 b are sectional views respectively illustrating different embodiments of cogging generating protrusions according to the present invention.
  • FIGS. 5 a to 5 c are diagrams respectively illustrating waveforms of cogging torques according to various shapes of cogging generating protrusions according to the present invention.
  • FIG. 7 is a view illustrating an armature coil having straight sides in accordance with the present invention.
  • FIGS. 10 to 12 are views respectively illustrating various examples of conventional cogging generating protrusions.
  • the motor includes a housing 1 constituting a lower portion of the motor, and a rotor 3 constituting an upper portion of the motor and arranged over the housing 1 .
  • the rotor 3 is rotatably coupled at its central portion to the central portion of the housing 1 by means of a shaft 2 .
  • the shaft 2 is fixedly mounted at its upper end to the lower surface of the rotor 3 .
  • the shaft 2 extends downwardly through a hollow bearing holder 11 upwardly protruded from the central portion of the housing 1 in such a fashion that it is rotatably supported by bearings 5 mounted in the bearing holder 11 .
  • the rotor 3 is a rotating member for the motor.
  • a rotor magnet 32 is mounted on the lower surface of the rotor 3 by means of a magnetic yoke 32 attached to the rotor 3 .
  • the rotor magnet 32 has a flat annular shape and is provided with a plurality of alternating N and S poles. The number of poles in the rotor magnet 32 corresponds to 2P, where P is an integer not less than 1.
  • the bearing holder 11 which has a hollow structure, is upwardly protruded from the central portion of the housing 1 .
  • the upper end of the bearing holder 11 has a reduced diameter as compared to the lower end of the bearing holder 11 so that it has a stepped structure in order to seat a stator 4 thereon.
  • the stator 4 mainly includes a printed circuit board 41 , a stator yoke 42 laid on the printed circuit board 41 , and an armature coil 43 attached to the upper surface of the stator yoke 42 .
  • the printed circuit board 41 of the stator 4 serves to supply single-phase current from an external source to the armature coil 43 via circuits patterned on opposite surfaces thereof.
  • the stator yoke 42 is a conductive flat plate laid on the printed circuit board 41 in such a fashion that it faces the rotor magnet 32 .
  • the armature coil 43 which is attached to the upper surface of the stator yoke 42 , interacts with the rotor magnet 32 , thereby generating an electromagnetic force.
  • FIGS. 3 a to 3 d illustrate various embodiments of the armature coil according to the present invention, respectively.
  • the armature coil 43 has a closed loop structure having a plurality of uniformly spaced apexes.
  • a cogging generating protrusion 44 is protruded from the stator yoke 42 at a position spaced from an associated one of the apexes of the armature coil 43 by a desired angle.
  • the cogging generating protrusion 44 serves as a load against a coil torque generated by virtue of an electromagnetic force interacting between the armature coil 43 and rotor magnet 32 .
  • the number of apexes in the armature coil 43 corresponds to 1 ⁇ 2 of the number of poles in the rotor magnet 32 .
  • the number of cogging generating protrusions 44 each being positioned at an angle from an associated one of the apexes of the armature coil 32 also corresponds to 1 ⁇ 2 of the number of poles in the rotor magnet 32 .
  • the armature coil 43 has 3 apexes corresponding to 1 ⁇ 2 of the 6 poles. Where the rotor magnet 32 has 8 poles, the armature coil 43 has 4 apexes. For a rotor magnet having 10 or 12 poles, the armature coil 43 has a closed loop shape having 5 or 6 apexes.
  • the armature coil 43 has sides each connecting neighboring apexes while being radially inwardly curved with a desired radius of curvature.
  • the armature coil 43 may have straight sides in accordance with the present invention, as shown in FIG. 7 .
  • Each side of the armature coil 43 has a length not more than the pole width of the rotor magnet 32 .
  • Each cogging generating protrusion 44 is arranged at a position spaced from an associated one of the apexes of the armature coil 43 by a desired angle in a rotation direction of the rotor magnet 32 without overlapping with the armature coil 43 .
  • the angle of each cogging generating protrusion 44 from the associated apex of the armature coil 43 corresponds to 1 ⁇ 4 of the angular width of one pole in the rotor magnet 32 .
  • the angular width of one pole in the rotor magnet 32 correspond. to the value obtained by dividing 360°, namely, the sum of angular widths of all poles in the rotor magnet 32 , by the number of poles.
  • each cogging generating protrusion 44 from the associated apex of the armature coil 43 is 15° obtained by dividing the pole width of 60° by 4. That is, each cogging generating protrusion 44 is arranged at a position shifted by an angle of 15° from the associated apex of the armature coil 43 in the rotation direction of the rotor magnet 32 .
  • each cogging generating protrusion 44 is spaced from the associated apex of the armature coil 43 by angles of 11.25°, 9°, and 7.5°, respectively.
  • the cogging generating protrusions 44 may be formed by partially cutting out the stator yoke 42 having a flat plate structure and upwardly bending desired portions of the stator yoke 42 at the edges of the cutouts in such a fashion that the upper end of the bent portions are arranged near the rotor magnet 32 .
  • the cogging generating protrusions 44 may be integrally formed with the stator yoke 42 in such a fashion that they are upwardly protruded from the upper surface of the stator yoke 42 , when the stator yoke 42 is molded.
  • a dead point where the coil torque generated between the rotor magnet 32 and armature coil 43 during the rotation of the rotor becomes zero, is always formed at a fixed point spaced from each apex of the armature coil 43 by a constant angle.
  • each cogging generating protrusion 44 varies in various forms depending on different protruded structures of the cogging generating protrusion 44 , as shown in FIGS. 5 a to 5 c . Accordingly, it is possible to effectively apply the present invention to a variety of motors having different magnetized structures for the rotor magnet by selecting an appropriate protruded structure of the cogging generating protrusion 44 in accordance with the magnetized structure of the motor to which the present invention is applied.
  • the output form of the coil torque varies correspondingly.
  • it is required to generate a cogging torque having an output form exhibiting the same variation as the output form of the coil torque. In accordance with the present invention, this can be easily achieved by simply varying the protruded structure of the cogging generating protrusion 44 .
  • the height b of the cogging generating protrusion 44 determines the magnitude of the cogging torque whereas the width a of the cogging generating protrusion 44 determines an electrical angle at which a cogging is generated.
  • the electrical angle corresponds to the sum of angles of two poles in the rotor magnet.
  • the width a at the tip of the cogging generating protrusion 44 determines a variation in peak cogging torque. In accordance with the present invention, therefore, a cogging torque matching with the coil torque generated is generated by appropriately combining together the above mentioned design parameters for the cogging generating protrusion.
  • the output pattern of the cogging torque varies depending on the material of the cogging generating protrusion 44 as well as the size of the cogging generating protrusion 44 , namely, the width a and height b. Accordingly, the size and material of the cogging generating protrusion 44 are appropriately adjusted to output a cogging torque matching with the coil torque generated, thereby generating an ideal resultant torque.
  • the sides of the armature coil 43 connecting neighboring apexes have a curved shape rather than a straight shape, as shown in FIG. 6 . It is more preferable that the inner surface of each curved side of the armature coil 43 extends radially inwardly to the inner peripheral surface of the rotor magnet 32 when viewed in a plan view.
  • F IL ⁇ B
  • the effective radial length L of the armature coil, where the sides connecting neighboring apexes have a curved shape is longer than the effective radial length l of the armature coil where the sides have a straight shape.
  • the sides connecting neighboring apexes have a curved shape, accordingly, there is an advantage in that a higher coil torque can be obtained using a relatively reduced amount of supply current, I, thereby preventing loss of current.
  • each cogging generating protrusion 44 provided at the stator yoke 42 is arranged at a position, where it can come into contact with the armature coil 43 , it serves as a guide upon coupling the armature coil 43 . In this case, accordingly, the coupling of the armature coil 43 can be accurately achieved without using any jig.
  • the cogging generating protrusions 44 also serves to prevent the coupled armature coil 43 from moving. Accordingly, a more stable workability is provided when the stator yoke 42 and armature coil 43 are fixed to each other by means of an adhesive.
  • the armature coil 43 comprises a single coil having a closed loop shape in accordance with the present invention, the fabrication thereof can be simplified. It is also possible to greatly reduce loss of an electromagnetic force generated between the rotor magnet 32 and armature coil 43 , thereby maximizing the torque efficiency of the motor.
  • the cogging generating protrusions 44 are integrally formed with the stator yoke 42 . Accordingly, the number of processes for forming the cogging generating protrusions 44 is reduced. Furthermore, the variation in the shape and size of the cogging generating protrusions 44 can be more freely achieved. Accordingly, it is very easy to cope with a change in the use purpose of the motor or a variation in the magnetized structure of the rotor magnet.
  • the formation of the cogging generating protrusions 44 is carried out simultaneously with the fabrication of the stator yoke 42 in accordance with the present invention. Accordingly, there is a great advantage in terms of a mass production. Since the cogging generating protrusions 44 can serve as a guide upon coupling the armature coil 43 to the stator yoke 42 , this coupling can be more accurately achieved. As a result, an enhancement in productivity is obtained.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Permanent Magnet Type Synchronous Machine (AREA)
  • Brushless Motors (AREA)
  • Iron Core Of Rotating Electric Machines (AREA)
US09/191,993 1997-11-13 1998-11-13 Disk-type brushless single-phase DC motor Expired - Fee Related US6172442B1 (en)

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KR97-59706 1997-11-13
KR19970059706 1997-11-13

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Cited By (19)

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US6462441B1 (en) * 2001-02-14 2002-10-08 Sunonwealth Electric Machine Industry Co., Ltd. Rotor assembly of brushless direct current motor
US20020175588A1 (en) * 2001-05-24 2002-11-28 Rajasingham Arjuna Indraes Waran Axial gap electrical machine
EP1280260A2 (en) 2001-05-24 2003-01-29 Arjuna Indraeswaren Dr. Rajasingham Axial gap electrical machine
US6517326B2 (en) * 2000-04-14 2003-02-11 Matsushita Electric Industrial Co., Ltd. Blowing apparatus
US6700278B1 (en) * 1999-01-22 2004-03-02 Institute Fur Mikrotechnik Mainz Gmbh Disk motor with bearing prestressing feature
EP1480317A2 (de) 2003-05-19 2004-11-24 Robert Bosch Gmbh Elektrische Maschine in Axialflussbauweise
US20080048532A1 (en) * 2006-08-28 2008-02-28 Adda Corp. Magnetic force sensing device in a brushless motor to enhance magnetic force sensibility of a hall element inside the brushless motor
US20080277094A1 (en) * 2007-05-10 2008-11-13 Industrial Technology Research Institute Miniature heat-dissipating fan device
US20100303652A1 (en) * 2007-05-10 2010-12-02 Industrial Technology Research Institute Miniature heat-dissipating fan device
US20100308684A1 (en) * 2008-01-18 2010-12-09 Alex Horng Motor with Detacthable Winding Assemblies
CN101363444B (zh) * 2007-08-06 2011-10-12 财团法人工业技术研究院 微散热风扇装置
US20130313935A1 (en) * 2012-05-22 2013-11-28 Nidec Corporation Brushless motor and disk drive apparatus
US20140062087A1 (en) * 2012-09-05 2014-03-06 Mustafa I. Beyaz Ball bearing supported electromagnetic microgenerator
US20160065017A1 (en) * 2014-08-29 2016-03-03 Minebea Co., Ltd. Brushless motor
CN109996159A (zh) * 2017-12-30 2019-07-09 美商楼氏电子有限公司 电声换能器
US10523085B2 (en) * 2015-08-03 2019-12-31 Nidec Seimitsu Corporation Vibration motor
US10530218B2 (en) * 2015-08-03 2020-01-07 Nidec Seimitsu Corporation Vibration motor
US11018540B2 (en) * 2016-04-19 2021-05-25 Amotech Co., Ltd. Slim-type stator, and single phase motor and cooling fan using same
US20220352799A1 (en) * 2021-04-30 2022-11-03 Seiko Epson Corporation Rotary motor and robot arm

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KR100312343B1 (ko) * 1998-12-31 2001-12-28 이형도 단상의브러쉬레스팬모터
KR20020085430A (ko) * 2001-05-08 2002-11-16 (주)오리엔트텔레콤 기동전압이 개선된 단상 브러시리스 직류 팬모터
KR101105060B1 (ko) * 2009-11-23 2012-01-13 엘지이노텍 주식회사 진동 액츄에이터

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4620139A (en) 1985-07-22 1986-10-28 Kabushiki Kaisha Shicoh Giken Brushless d.c. motor
US4704566A (en) * 1986-06-19 1987-11-03 Shicoh Engineering Co., Ltd. Self-starting disk-type brushless motor with screw projection for generating cogging
US4725752A (en) * 1986-09-22 1988-02-16 Shicoh Engineering Co., Ltd. 1-phase self starting disk-type brushless motor with cogging element
US4733119A (en) * 1986-09-22 1988-03-22 Shicoh Engineering Co., Ltd. 1-Phase self-starting disk-type brushless motor with cogging-producing element
US4757222A (en) 1984-07-11 1988-07-12 Shicoh Engineering Co., Ltd. 1-phase energized disk-type brushless motor
US4973869A (en) * 1988-07-29 1990-11-27 Samsung Electro-Mechanics Co., Ltd. Brushless coreless DC motor
US5097170A (en) * 1988-02-05 1992-03-17 Johnson Electric S.A. Brushless d.c. electric motor
US5101131A (en) * 1986-12-19 1992-03-31 Canon Kabushiki Kaisha Brushless motor
JPH07213041A (ja) 1994-01-18 1995-08-11 Shicoh Eng Co Ltd 単相ブラシレスモ−タ

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4757222A (en) 1984-07-11 1988-07-12 Shicoh Engineering Co., Ltd. 1-phase energized disk-type brushless motor
US4891537A (en) * 1984-11-07 1990-01-02 Shicoh Engineering Co. Ltd. 1-Phase energized disk-type brushless motor
US4620139A (en) 1985-07-22 1986-10-28 Kabushiki Kaisha Shicoh Giken Brushless d.c. motor
US4704566A (en) * 1986-06-19 1987-11-03 Shicoh Engineering Co., Ltd. Self-starting disk-type brushless motor with screw projection for generating cogging
US4725752A (en) * 1986-09-22 1988-02-16 Shicoh Engineering Co., Ltd. 1-phase self starting disk-type brushless motor with cogging element
US4733119A (en) * 1986-09-22 1988-03-22 Shicoh Engineering Co., Ltd. 1-Phase self-starting disk-type brushless motor with cogging-producing element
US5101131A (en) * 1986-12-19 1992-03-31 Canon Kabushiki Kaisha Brushless motor
US5097170A (en) * 1988-02-05 1992-03-17 Johnson Electric S.A. Brushless d.c. electric motor
US4973869A (en) * 1988-07-29 1990-11-27 Samsung Electro-Mechanics Co., Ltd. Brushless coreless DC motor
JPH07213041A (ja) 1994-01-18 1995-08-11 Shicoh Eng Co Ltd 単相ブラシレスモ−タ

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Patent Abstracts of Japan of JP 07 21 3041 of Aug. 1995.

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6700278B1 (en) * 1999-01-22 2004-03-02 Institute Fur Mikrotechnik Mainz Gmbh Disk motor with bearing prestressing feature
US6517326B2 (en) * 2000-04-14 2003-02-11 Matsushita Electric Industrial Co., Ltd. Blowing apparatus
US6462441B1 (en) * 2001-02-14 2002-10-08 Sunonwealth Electric Machine Industry Co., Ltd. Rotor assembly of brushless direct current motor
US7148594B2 (en) * 2001-05-24 2006-12-12 Millennium Motor Company Axial gap electrical machine
US20020175588A1 (en) * 2001-05-24 2002-11-28 Rajasingham Arjuna Indraes Waran Axial gap electrical machine
EP1280260A2 (en) 2001-05-24 2003-01-29 Arjuna Indraeswaren Dr. Rajasingham Axial gap electrical machine
US20030132045A1 (en) * 2001-05-24 2003-07-17 Rajasingham Arjuna Indraeswaran Axial gap electrical machine
US7098566B2 (en) * 2001-05-24 2006-08-29 Rajasingham Arjuna Indraes War Axial gap electrical machine
EP1480317A2 (de) 2003-05-19 2004-11-24 Robert Bosch Gmbh Elektrische Maschine in Axialflussbauweise
US20080048532A1 (en) * 2006-08-28 2008-02-28 Adda Corp. Magnetic force sensing device in a brushless motor to enhance magnetic force sensibility of a hall element inside the brushless motor
US20080277094A1 (en) * 2007-05-10 2008-11-13 Industrial Technology Research Institute Miniature heat-dissipating fan device
US20100303652A1 (en) * 2007-05-10 2010-12-02 Industrial Technology Research Institute Miniature heat-dissipating fan device
CN101363444B (zh) * 2007-08-06 2011-10-12 财团法人工业技术研究院 微散热风扇装置
US20100308684A1 (en) * 2008-01-18 2010-12-09 Alex Horng Motor with Detacthable Winding Assemblies
US9667108B2 (en) * 2012-05-22 2017-05-30 Nidec Corporation Brushless motor and disk drive apparatus
US9209656B2 (en) * 2012-05-22 2015-12-08 Nidec Corporation Brushless motor and disk drive apparatus
US20160056675A1 (en) * 2012-05-22 2016-02-25 Nidec Corporation Brushless motor and disk drive apparatus
US20130313935A1 (en) * 2012-05-22 2013-11-28 Nidec Corporation Brushless motor and disk drive apparatus
US20140062087A1 (en) * 2012-09-05 2014-03-06 Mustafa I. Beyaz Ball bearing supported electromagnetic microgenerator
US9083208B2 (en) * 2012-09-05 2015-07-14 The United States Of America As Represented By The Secretary Of The Army Ball bearing supported electromagnetic microgenerator
US20160065017A1 (en) * 2014-08-29 2016-03-03 Minebea Co., Ltd. Brushless motor
US9755478B2 (en) * 2014-08-29 2017-09-05 Minebea Co., Ltd. Brushless motor
US10523085B2 (en) * 2015-08-03 2019-12-31 Nidec Seimitsu Corporation Vibration motor
US10530218B2 (en) * 2015-08-03 2020-01-07 Nidec Seimitsu Corporation Vibration motor
US11018540B2 (en) * 2016-04-19 2021-05-25 Amotech Co., Ltd. Slim-type stator, and single phase motor and cooling fan using same
CN109996159A (zh) * 2017-12-30 2019-07-09 美商楼氏电子有限公司 电声换能器
US20220352799A1 (en) * 2021-04-30 2022-11-03 Seiko Epson Corporation Rotary motor and robot arm

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KR100284873B1 (ko) 2001-03-15
JP3023094B2 (ja) 2000-03-21
KR19990045249A (ko) 1999-06-25
JPH11220864A (ja) 1999-08-10

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